Rockwell Automation 1771-QDC, D17716.5.85(Passport) MNL. PLASTIC MOLDING MODULE - Manual (Page 16)

Overview of Inject Mode
Chapter 1
1-5
InjectionĆtoĆpack Transition
The QDC module ends the injection phase and automatically starts the
pack or hold phase when it detects the first of up to four events occurred:
Ram (screw) position exceeds a preset limit
Ram (screw) pressure exceeds a preset limit
Cavity pressure exceeds a preset limit
Injection phase elapsed time exceeds a preset limit
You select which of these events you want monitored for transition by
entering the appropriate setpoint, or zero for ignoring the event. You also
may specify the zone of ram (screw) travel over which pressure transitions
may or may not occur.
Pack Phase
The QDC module controls the pack phase with a pressure vs. time profile.
You create the profile based on controlling hydraulic pressure against the
ram (screw), or by controlling pressure within the mold cavity resulting
from hydraulic pressure against the ram (screw). You can control either
pressure with up to five time segments. By convention, events occur from
right to left on the time axis (figure 1.5). You determine the pressure
setpoints and time durations for the pack profile based on molding
requirements. The pack phase is optional.
Figure 1.5
Pack Phase Example
Pressure
Time
1 2 3 4 5